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I have to work with the image acquisition toolbox in Matlab and I find it quite disturbing to always change to windows. So I installed Matlab 2010b on my Linux machine (Arch, Kernel 39). Skype & friends work perfectly with my camera (using uvcvideo/video4linux2) but Matlab doesn't. It is a built-in laptop camera and I (my user) am in the video group.

Matlab says

>> imaqhwinfo
ans =
    InstalledAdaptors: {}
        MATLABVersion: '7.11 (R2010b)'
          ToolboxName: 'Image Acquisition Toolbox'
        ToolboxVersion: '4.0 (R2010b)'

Googeling just told me, that the toolbox should support video4linux2 and that I should not run into problems if the camera can be used by other software.

It might be important, that I use Matlab 64 bit while "lsmod | grep v4l2" says:

v4l2_compat_ioctl32     8364  1 videodev

Does this mean that my video4linux2 driver is 32 bit?

share|improve this question
compat_ioctl suggests that the driver is in fact for 64-bit kernels to accommodate 32-bit programs, so (if that is indeed what the name means here) it's just irrelevant. It shouldn't matter that Matlab is 64-bit, but the driver could be buggy. Can you check that the webcam with a 64-bit application (cheese, webcam, motion, whatever you have convenient)? – Gilles Jun 21 '11 at 20:43
cheese works. As does skype. – janoliver Jun 21 '11 at 22:22

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